2025/05/13 by Pedro da Silveira Ferreira, Ferreira, Pedro da Silveira, Stephen Owusu +1
Physics and Astronomy · #Cosmology and Nongalactic Astrophysics (astro-ph.CO) #FOS: Physical sciences #astro-ph.CO
paper · pdf · doi:10.48550/arxiv.2505.08761
24 pages, 4 figures
arxiv created 2026/05/07 · arxiv updated 2026/08/04
We forecast the detectability of the lensing footprint of a collapsing cosmic texture, a topological defect proposed as an explanation of the CMB Cold Spot. Our pipeline is a quadratic, template-amplitude estimator for localized, azimuthally symmetric lensing profiles: it projects the standard off-diagonal covariance response of lensed CMB fields onto a physically motivated template. Rather than reconstructing an arbitrary lensing field, the method targets weak but coherent localized footprints from sources such as voids, clusters and topological defects. Using the temperature/polarization pairs TT, TE+ET, EE, TB+BT and EB+BE for forthcoming Simons Observatory data, we estimate a 2.3σ detection if the texture amplitude reaches the current Planck 2018 2σ upper limit, and a 1.5σ measurement for the best-fit texture parameters. This sensitivity is notable given the expected typical deflection angle below 6''. The inclusion of polarization substantially increases the cumulative signal-to-noise ratio, by ∼67% relative to temperature alone, making sub-10'' localized lensing footprints accessible to SO-like surveys.